For the same price - or less - you can get any of many "multipurpose printer/scanner/fax" machines that will scan a full page in one pass. Many of these can be set up to scan directly to your "photo" program where you can zoom to any size you want.

"Manual scanners" have been around at least since the Logitec unit we had before page scanners were affordable (ca. 1992?) and are probably much better now, but scanning in "scraps" makes for difficult OCR conversion. Accurate OCR generally requires accurate alignment with the "lines" of text being converted. Consistent alignment, and even just straight lines, are very difficult to obtain with a "manual drive" scanner.

Most good OCR programs require that the image be saved before conversion, so this scanner wouldn't have much to offer, relative to a good page scanner, other than perhaps portability, if you're using one of the common OCR programs. There may be OCR programs that have "on the fly" capabilities - convert without saving first, but I haven't looked for that capability and it's not present in the OCR programs I've used.

Anything displayed on the monitor can be "captured" in Windows using Alt-PrtScn or Ctl-PrtScn and pasting into a program capable of saving a picture, so it's not absolutely necessary that the "mouse scanner" be able to do that for you, although at high magnification each picture will contain fairly small bits of text.

Instead of straining to read and then scanning the bits I want to keep through a flat bed scanner I'd suggest scanning directly to a photo program, zoom and read what you want, and close without saving if you don't want to keep it. Save the scan only if you want to keep it. Use OCR on the saved scan only if you need a "text version."

John